acpi_numa.c

  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * ACPI 5.1 based NUMA setup for ARM64
  4 * Lots of code was borrowed from arch/x86/mm/srat.c
  5 *
  6 * Copyright 2004 Andi Kleen, SuSE Labs.
  7 * Copyright (C) 2013-2016, Linaro Ltd.
  8 *		Author: Hanjun Guo <hanjun.guo@linaro.org>
  9 *
 10 * Reads the ACPI SRAT table to figure out what memory belongs to which CPUs.
 11 *
 12 * Called from acpi_numa_init while reading the SRAT and SLIT tables.
 13 * Assumes all memory regions belonging to a single proximity domain
 14 * are in one chunk. Holes between them will be included in the node.
 15 */
 16
 17#define pr_fmt(fmt) "ACPI: NUMA: " fmt
 18
 19#include <linux/acpi.h>
 20#include <linux/bitmap.h>
 21#include <linux/kernel.h>
 22#include <linux/mm.h>
 23#include <linux/memblock.h>
 24#include <linux/mmzone.h>
 25#include <linux/module.h>
 26#include <linux/topology.h>
 27
 28#include <asm/numa.h>
 29
 30static int acpi_early_node_map[NR_CPUS] __initdata = { [0 ... NR_CPUS - 1] = NUMA_NO_NODE };
 31
 32int __init acpi_numa_get_nid(unsigned int cpu)
 33{
 34	return acpi_early_node_map[cpu];
 35}
 36
 37static int __init acpi_parse_gicc_pxm(union acpi_subtable_headers *header,
 38				      const unsigned long end)
 39{
 40	struct acpi_srat_gicc_affinity *pa;
 41	int cpu, pxm, node;
 42
 43	if (srat_disabled())
 44		return -EINVAL;
 45
 46	pa = (struct acpi_srat_gicc_affinity *)header;
 47	if (!pa)
 48		return -EINVAL;
 49
 50	if (!(pa->flags & ACPI_SRAT_GICC_ENABLED))
 51		return 0;
 52
 53	pxm = pa->proximity_domain;
 54	node = pxm_to_node(pxm);
 55
 56	/*
 57	 * If we can't map the UID to a logical cpu this
 58	 * means that the UID is not part of possible cpus
 59	 * so we do not need a NUMA mapping for it, skip
 60	 * the SRAT entry and keep parsing.
 61	 */
 62	cpu = get_cpu_for_acpi_id(pa->acpi_processor_uid);
 63	if (cpu < 0)
 64		return 0;
 65
 66	acpi_early_node_map[cpu] = node;
 67	pr_info("SRAT: PXM %d -> MPIDR 0x%llx -> Node %d\n", pxm,
 68		cpu_logical_map(cpu), node);
 69
 70	return 0;
 71}
 72
 73void __init acpi_map_cpus_to_nodes(void)
 74{
 75	acpi_table_parse_entries(ACPI_SIG_SRAT, sizeof(struct acpi_table_srat),
 76					    ACPI_SRAT_TYPE_GICC_AFFINITY,
 77					    acpi_parse_gicc_pxm, 0);
 78}
 79
 80/* Callback for Proximity Domain -> ACPI processor UID mapping */
 81void __init acpi_numa_gicc_affinity_init(struct acpi_srat_gicc_affinity *pa)
 82{
 83	int pxm, node;
 84
 85	if (srat_disabled())
 86		return;
 87
 88	if (pa->header.length < sizeof(struct acpi_srat_gicc_affinity)) {
 89		pr_err("SRAT: Invalid SRAT header length: %d\n",
 90			pa->header.length);
 91		bad_srat();
 92		return;
 93	}
 94
 95	if (!(pa->flags & ACPI_SRAT_GICC_ENABLED))
 96		return;
 97
 98	pxm = pa->proximity_domain;
 99	node = acpi_map_pxm_to_node(pxm);
100
101	if (node == NUMA_NO_NODE) {
102		pr_err("SRAT: Too many proximity domains %d\n", pxm);
103		bad_srat();
104		return;
105	}
106
107	node_set(node, numa_nodes_parsed);
108}
109